Performance analysis and multi-objective optimization of ORC system driven by low temperature flue gas waste heat
The flue gas waste heat at the fourth stage exit of annular cooler equipped with 360 m2 sintering machine was taken as the research object,and the circulating water heated through the flue gas heat exchanger was selected as the heat source of organic Rankine cycle(ORC)system.The thermal and economic models of system were established firstly,and the effects of ORC thermodynamic parameters on the system thermal performance and economic performance under different working mediums were investigated.Furthermore,a multi-objective optimization method based on the genetic algorithm was adopted to determine the optimal cycle working medium of ORC system,as well as the best thermal performance and economic performance.The results indicate that,the smaller the superheat degree and pinch-point temperature difference in evaporator are,and the higher the evaporation temperature is,the larger the system exergy efficiency is.The system electricity production cost gradually reduces with rising the evaporation temperature,and reduces first and then rises with rising the superheat degree and pinch-point temperature difference in evaporator.When the system thermal parameters are optimum,the system exergy efficiency and electricity production cost of R245fa are better than those of R600a and R236ea,so it should be preferentially selected as the circulating working medium of ORC system driven by the low temperature sinter flue gas waste heat.At this time,the maximum exergy efficiency of ORC system is 46.34％,and the minimum electricity production cost is 0.12123 $/(kW·h).
annular coolerwaste heat recoveryorganic Rankine cycleexergy efficiencyelectricity production costgenetic algorithm
万方数据
维普
